The present invention relates to signal conditioning circuits. More particularly, it relates to characterizing signals to enhance the availability of the data content thereof.
In the art of data acquisition and utilization, it has been found that the acquired data has a wider dynamic range than can be accommodated by the utilization apparatus. One instance of such a system is seen in certain medical investigatory techniques. For example a technique for non-invasive examination of internal bodily organs is accomplished through the use of ultrasonic probes which transmit sonic pulses into the body and responds to echoes from tissue interfaces within the body. The echo signals detected by the transducer have a dynamic range that is significantly greater than can be accommodated by a cathode ray tube display device or by an associated hard copy recorder. In order that the low level signals may be raised to a useful level, the detected signals are amplified to the point necessary for the recognition of such low level signals. In such systems, it is usual to employ a compression system which may, in fact, involve a logarithmic compression amplifier which compresses the high level signals. In such systems, the high level signals are frequently merged into an indistinguishable blur. It has been found, however, that the medical practitioners utilizing such devices, are not only interested in a recognizable definition of the low level signals, but are also keenly interested in a sharp definition of the high level signals.